It is a requirement to individually handle individual integrated circuit die after they have been separated from a wafer. This process is often referred to as die picking. A problem exists, however, as it is typically undesirable to physically contact the top, circuitry containing surface of the die, as damage may result to the delicate and critical top surface features.
In U.S. Pat. No. 6,024,631, issued Feb. 15, 2000, entitled “Method and Apparatus to Hold Integrated Circuit Chips onto a Chuck and to Simultaneously Remove Multiple Integrated Circuit Chips from a Cutting Chuck”, Piper discloses a cutting chuck used with a cutting blade for holding a semiconductor wafer in place during a dicing process. Piper also discloses a die pick for picking the segmented semiconductor wafer from the chuck. The die pick includes a pick head having a surface for contacting the plurality of die sawn from a wafer. The surface includes a plurality of ports that are in fluid communication with a vacuum source, and the die pick simultaneously picks the plurality of die from the chuck for further processing.
The technique of Piper is one that is exemplary of the prior art die pickers that require contact to the top surface of the die.
In U.S. Pat. No. 5,169,196, issued Dec. 8, 1992, entitled “Non-Contact Pick-Up  Head”, Safabakhsh discloses a pick-up tool or pick-up head for picking up semiconductor objects. An active face of the pick-up tool is provided with an outer plenum that extends around the peripheral edges of the object to be picked up and further includes an inner plenum formed in the center of the pick-up tool over the object to be picked up. A partial vacuum is applied to the inner plenum and compressed air is supplied to the outer plenum. The compressed air flows over a support ridge separating the inner plenum from the outer plenum. The air flowing over the ridge generates a thin air film supporting layer so that the object being picked up by the pick-up tool is supported on the air film and levitated separate and apart from the pick-up tool.
As can be appreciated, the pick-up tool of Safabakhsh has a complicated construction, and furthermore requires both a source of compressed air and a partial vacuum source for operation.